System of control for electric motors.



A. J. HORTON. SYSTEM OF CONTROL FOR ELECTRIC MOTORS. APTLICATIONIIILED OCT. 8, 1903.

1,027,846. Patented Ma 28, 1912.

UNITED STATES PATENT orrrcn ALBERT J. HORTON, 01 WHITE PLAINS, NEW YORK, ASSIGNOB TO THE CUTLER- HAHEB MIG. 60., OF M'ILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

SYSTEM OF OON'IBOL FOR ELECTRIC MOTORS.

Specification otLetters Patent.

- Patented na eaiem.

To all whom it may concem:

Be it known that I, ALBERT J. HORTON, a citizen of the United States, residing at White Plains, in the county of Westchester and State of New York, have invented new and useful. Improvements in Systems of Control for Electric Motors, of which the following is a. full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to improvements in systems of control for electric motors, and .more particularly to means for causin a motor to operate either at normal spec or slow speed. 7 Such systems of control are commonly employed in connection with printing presses where it is desired to operate the press as slow speed for Oneob ect of my invention is to provlde means whereb the motor may be caused to run at norma speed by operatin the controlling arm of a rheostat or at s ow from points about'the press or other machine, when the rheostat arm is in a predetermined position, said rheostat arm having a 1 oil position for rendering closure of the motor circuit impossible.

Other objects and advantages will be hereinafter set forth. I

For the purpose: of more fully disclosing my invention I'have diagrammatically illustrated, in the accompanying drawing, a system of motor control embodying one .form' 35 thereof. Of course, other systems embodyin my invention may be developed.

he system which I have shown. for the purpose of illustration, includes a main switch 1, carried by the pllunger 2 of a solenoid 3. The main switc is provided with 'maincontacts 4 and 5- adapted to engage stationary contacts 6 and 7, respectively, and arcing contacts 8 and 9 which are adaptedto engage stationary arcing contacts 10 and 11, respectively. When the main switch is open the contacts 8 and 9 engage stationa contacts 12 and 13. At its upper end,

' the p unger 2 of the, solenoid 3, carries a tail rod 3' upon which is loosely mounted a contact disk 14, adapted to bridge contacts 15 and 16 when themain switch is open. The tail rod 3 carries a collar 3", so adjusted thereon as to engage and raise the disk 14 .from the contacts 15 and 16 when the core? has been sufliciently raised to close the mam inching.

speed,

switch. I also provide a rheostat having a movable controlling arm 17 which is provided with an operating handle 18. The. arm. 17 carries brushes 19 and 20. brush 20 is adapted to be moved over a series of contacts 21, while the brush 19 is adapt ed to be moved over contacts 22, 23. and 24 and contact segment 25. The contacts 22, 23 and 24 and the contact segment 25 are so arranged that when the arm-17 is in. its initial position, the brush 19 w. tact 22. When brush 20 engages of the series of contacts 21, the brush 19 engages contact 23 and when the brush 26 engages the third of the series of contacts 21, the brush 19 engages the contact segment 25 and contact 24. During the continued movement of the arm 17 to the rightthe brush 19 engages the contact se ment 25.

The motor illustrated is o the shuntwound type bein provided with an armature a and shunt-iield winding f. Of course, the motor may be of any preferred type. One terminal of the armature a is connected by conductor 26 to main line 27 The opposite terminal of the motor armature is connected by conductor 29 to contact 6. Contact 7 is connected by conductor 30 to the last of the series of contacts 21. All but-the first three of the series of contacts 21 are connected to an armature resistance 31. The first of the series "of contacts 21 is dead, while the second, third and fourth are electrically connected. The arm 17 is connected by conductor 32 to main line 28. One terminal of the shunt-field winding 1 is connected by conductor 33 to conductor 32, while the opposite terminal of said winding is connected by conductor 34 to conductor 26. Contact 13 is connected by conductor 35 to conductor 29'. Contact 12 is connected by conductor 36, through a resistance 37 to conductor 26. Contact 15 is connected by conductor 38 to contact 24.- Contact segment 25 is connected by conductor 39, through a resistance 40, to contact 16. Contact 16 is connected by conductors 41 and 42 through push-buttons 43, by conductor 44, to one terminal of the solenoid winding 3. The opposite terminal of the winding 3 is connected by conductor 45 to main line 27. Contact 23 is connected by conductors 46 and 47 to contact 48. The push-buttons 43 tend to stand in the position shown, but are adapted to be moved into engagement with the contacts 48.

While l have shown only two push-buttons it'should be understood that any number of the same may be provided, and may be placed in any desirable location.

I shall now describe the operation of this system. a

. Assuming that the arm 17 of the rheostat is in itsextreme left-hand position, the brush 20, carried thereby, will engage the firstof the series of contacts 21, while the brush 19 will engage contact 22. Inasmuch as both of these-contacts are' dead the motor cirouit will be open. Assuming now that the farm 17 be moved so that the brush 20, carried: thereby, will engage the second of the s'eries'of contacts 21 and the brush 19 will engage contact 23, circuit may be closed through the operating winding of the main switch by'moving either of the push-buttons i?) int'o 'engagement with one of the contacts 48; lfThe circuit for the winding 3,

rhaythen'be traced from main line-28, by conductor 32, through the arm 17 and brush 19 t6 contact 23, thenceby conductors 46 and trams of the contacts 48, through one of the" push-buttons 43, by conductor 44, through the winding 3 and by conductor 45 to main line 27. As soon as the circuit of the winding 3 is closed, said winding will respond and 'close the main switch. The motor circuit may then be traced, as already described, to the arm 17 by brush to the second of the series of contacts '21, through all of the'resistance 31,: by conductor 27 and 30 to contact 7, across main switch 1 to contactd, by conductor 29 through the armature a, and by conductor 26 to main line 27 inasmuch as the shunt-field winding f is connected' directly across the main line, the motor is'started'under full field strength. The circuit for the shunt-field winding f may be traced from main line 28, by conductor-33, through the winding 7", by conductors 34 and 26, to main line'27. It will thus be seen that'as long as the push-button this held inengagement with contact 38', the motor will operate at a slow speed with all of the resistance 31 in circuit. lh hen it is desired to stop the motor it is only necessaryto release the push-button &3, where upon the circuit of the winding 3 will be opened, thus permitting the main switch to open; With the arm 17 the position just described it willbe apparent that the motor may be'started and stopped any number oft-times lay-the operation of either of 'theush-=huttons-d3. As beore stated, any

num er of push-buttons may be provided and the same may be located in any convenient position. Assuming now that the arm 1 be moved farther to the right so that the brush .19 will engage contact segment 25 and contact24, and asg that the push-buttons 43 are in the position b ShOWDfthG circuit ofthe winding '3 will be to main line 27. The winding 3 will then again respond and close the main switch 1. As soon as the main switch 1 is closed, the

armature circuit will again be completed and may be traced, as already described. As soon' as the winding 3 responds to close the main switch the contact plate let is raised from the contacts 15 and 16. This results in opening the circuit for the winding 3 just described, but upon the opening of this circuit, a maintaining circuit is es tablished. This circuit'may be traced from brush 19 to contact segment 25, by conductor 39, through resistance to to contact 16, and thence through the winding 3, as already traced. This maintaining circuit ismaintained closed'du'ring the continued movement of the arm 1'? to the right. The

. resistance 40 in the maintaining circuit cuts down the flow of current through the winding 3 to an amount just suficient to cause said winding to maintain themain switch" closed, but prevents said winding from reolosing'said switch until after the removal of the resistance 40. As will be hereinafter explained, the resistance 40 is only short-circuited when the arm 17 is in such a posi- 7 tion as to insert all of the resistance 31in the armature circuit. Assuming now that the arm 17 is moved farther to the right it will gradually remove the starting resistance. 31 from the armature circuit, and when it reaches its extreme right-hand position, will remove all of said resistance from circuit and cause the motor to operate at normal speed. After the motor has been brought up to normal speed it may he stopped by returning the arm 1? to its i tial position, or by operating either of the push-buttons 43. By operating either of the push-buttons &3 the circuit or the solenoid winding 3 is opened, thus permitting the main switch to open. the main switch opens, the contacts 8 '9, car l thereby, engage contacts 32 and establishes a across the terminalsof the motor armature. Thiscircuit may be traced from one terminal'of the motor armature by conductors 2% and 35 to contact 13, across the main switch 1 to contact 12, by conductor 3%, through resistance 37, to the o posits terminal oi. the

armature. The esta lishment of this circuit quickly brings the motor to estate of rest. Assumin now that the-motor circuit has been 'opene without returning the arm 17 to initial position, the main switch cannot e again closed until said arm has hcen' moved to the left to bring the brush 19 dynamic breaking circuit render said auxi engagement with the contact 24 or the contact 23. As already stated, the contacts 23 and 24 are so located that the arm 17 must bemoved to-insertall of the resistance 31 beforethe brush 19 engages the same.

Having thus descr bed what I claim as new and Letters Patent, is:

1. In a motor controller, in combinatiom fl an automatic main switch, a resistance varyto be moved to cause@ switch, and auxiliary for. causingoperation of said main, switch when said element is in a predeter-. said element, when in in i-i ing element adapted operation of said main means mined position, tial position, being auxi i eration of said main switch.

ada ted to render sa d combination, switch for controlling rheostat having 'a movable element adapted to be moved to ener be operated to energize said main switch when said rheostat element is in a predetermined position, said rheostat element, when ininitial osition, being iary means ineffective to energize said main switch. a

3. In a controller for electric motors, in combination, an 'electroresponsive main switch for controlling the motor circuit, a rheostat having a movable element adapted to be moved to energize said main switch, and auxiliary controlling means adapted to be operated to energize said main switch when said rheostat element is ina predetermined position, saidrheostat element, when in initial position, and when moved beyond a predetermined point, being adapted torender said auxiliary means inefiective to enerat all times, to

gize said main switc .4. In a controller for electric motors, in combination, an electroresponsive main switch a rheostat having a movable element adapted to be ,0 erated, to causesaid main switch to respon and auxiliary means adapted to be operated, when said rlieostat element is in a predetermined position to cause said main switch to respond, said rheostat element, when in in'tial position and when moved beyond a predetermined oint, being adapted to render said auxiliar means inefiective to "energize said main switch, said auxiliary means i'ng1 adapted, be operated to eenergize said main switch. I

5. In a motor controller, in combination, an electrore's nsive main switch, one or more control ing switches therefor, and a rheo'stat having-a movable element adapted, when in one position, to establish circuit connections whereby any one of said controlling switches may be operated energize sai my invention, desire to secure 'by element, an

ary means ineffective to cause the op- I i switch ineffective 2'. In a controller for electric motors, in I an electroresponsive main combination,

the motor circuit, a

'ze said main switch, and auxiliary controlling means adapted to adapted to y a plural t each adapted to" becactuated to cause thi main switch, said rheostat element being movable to another position to energize said main switch without operation of said controlling switches and adapted, when in initial position, to render said controlling switches inefiective to energize said main switch. p p

6. In a controller for electric motors, in combination, a rheostat having a movable electroresponsive main switch adapted to element when in a predetermined position, one or more controlling switches adapted to be actuated to energize said main switch when said contro ling element is in another l position, said element, when in initial position, being adapted to render said main to close the motor circuit. .7. In a controller for electric motors, in an electroresponsive main be energized by said rheostat switch, a rheostat having a controlling ele- I ment movable to energize said main switch, one or more auxiliary switchesand circuit con-nections whereby said auxiliary switch, or-switches, may be operated to energize said main switch when said rheostat element is in a predetermined position, said rheostat element, when in initial position, being adapted to interrupt the motor'circuit.

8. In a controller for electric motors, combination, switch, one or more controlling switches, a rheostat having a movable element adapted to establish circuit connections whereby said controlling switch, or switches, may be operated to energize said main switch, sai d tial position and when moved beyond a predetermined point, to interrupt said circuit connections and a maintaining circuit for an electroi'esponsive main ioo rheostat element being adapted, when in imsaid 'electroresponsive switch controlled by said rheostat element.

9. In a controller for electric motors,

combination, an electroresponsive main switch, one or more controlling switches, and a rheostat having a movable element adapted to establish circuit connections whereby said controlling switch, or ma be operated to energize said main switch, said rheo'stat element being movable to ener ize said main switch without operation 0 switches, and being adapted, when in initial position and when moved beyond a predetermined point, to render said auxiliary switch, or switches,

said main switch.

switches,

said controlling switch, or'

12o inefie'ctive to energize 10-. In a motor controller, the combination with an electromagnetically operated mam switch, of a rheostat having a movable member'adapted, in one position, to interrupt the motor circuit of switches, energization of the operating windin said main switch when said movable memher is in another position, said movable member, when in a third posit-ion, being adapted to cause the energization of the opcrating winding oi? said inein switch, Y

11. In e motor controlier the combinetion with an eiectromegnetlceiiy operated main switch, of e rheostet having a controlling erni adap ed, to interrupt the motor circuit, and a plurality of switches tending to stand in e certain position, each of being adapted to ice actuated to cause the energization of the operating winding of said main switch when said rheost-et arm is in another position, said rheostet arm, when in a third position, being adapted to cause the energization of the operating winding of said niein switch and circuit connections whereby said iast mentioned switches may be actuated to sense the deenergizetion oi? the operating winding of said main switch when said riieostat arm is in said third position.

12. in a. motor controller, the combination switch, of a when in one position,-

se'id iost mentioned switches with an eiectromegneticeiiy operated main rheostet having a movable arm adapted, when in one POSiMOH, to interrupt the motor circuit, and e plurality of switches, each adapted to ice actuated to close the circuit of tile operating winding of said inein switch when said rheostat arm is in another position, said last mentioned switches tending to move'to a position to cause the deenergizetion oi the operating winding of said main switch, seid rheostot arm when in a third position, being adapted to close the circuit of the operating winding of said main switch, said last mentioned switches being included in circuit with the operating winding of said main switch in witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

ALBERT riosros.

Witnesses:

WIKLIAM L. CHARLES B. BAKER. 

